fix(voice): name the outline source that answered

The outline rungs recorded only the credit kind, so the voice area code
never saw 'openfreemap' or 'nominatim' and stored every such outline as
the Overpass rung, even with no Overpass configured. Voice geometry tagged
the source originally; the merge with main kept main's untagged rungs and
its test pinning the absence. The tag is restored and the test now asserts
it for both sources.

src/annotations/outlineRungs.js

@@ -290,6 +290,9 @@ export function createOutlineRungs({
       const patch = finish(fp, asScope);
       if (patch?.ring) {
         patch.outlineCredit = provider === 'openfreemap' ? 'tiles' : 'osm';
+        // Which source answered, so a stored area names it (OpenFreeMap or
+        // Nominatim) instead of defaulting to the Overpass rungs.
+        patch.outlineSource = provider;
         ctx.credit?.(patch.outlineCredit);
         // One line per answered outline, like the resolver's own trace.
         console.log(

src/annotations/outlineRungs.test.mjs

@@ -146,7 +146,7 @@ test('a street comes from tiles before the configured ladder, as merged ribbons'
   );
   assert.ok(result.ring.length > 6);
   assert.equal(result.polygons.length, 1);
-  assert.equal('outlineSource' in result, false);
+  assert.equal(result.outlineSource, 'openfreemap');
   assert.equal(run.calls.base, 0, 'the ladder is not consulted');
   assert.deepEqual(run.calls.finished, ['street']);
   assert.deepEqual(credits, ['tiles']);
@@ -416,6 +416,7 @@ test('a city with no configured Overpass is outlined by Nominatim', async () =>
   );
   assert.deepEqual(result.ring, ring);
   assert.equal(result.outlineCredit, 'osm');
+  assert.equal(result.outlineSource, 'nominatim');
   assert.deepEqual(nominatim.asks[0], {
     query: 'Toulouse',
     kind: 'city',